Christie published over eighty books and other works, mainly whodunits. While her work is not considered part of the literary canon, she is a major figure in detective fiction. In particular, The Murder of Roger Ackroyd is noted for its use of narrative and its twist on the established genre.

Most of her books and short stories have been filmed, some many times over (Murder on the Orient Express, Death on the Nile, 4.50 from Paddington). The BBC has produced television and radio versions of most of the Poirot and Marple stories. A later series of Poirot dramatizations starring David Suchet was made by Granada Television.

She also used the pen name Mary Westmacott for romantic novels. She was married to Sir Max Mallowan, a British archaeologist, which contributed background to several of her novels set in the Middle East. Other novels were set in Torquay, Devon, where she was born.

During World War I she worked as a pharmacist, a job that also influenced her work: many of the murders in her books are carried out with poison.

In December 1926 she disappeared for eleven days and caused quite a storm in the press. Opinions are still divided as to whether this was a publicity stunt or an emotional breakdown.

Famous characters include Hercule Poirot and Jane Marple. Her stage play The Mousetrap[?] holds the record for the longest run ever in London, opening in London in November 1952 and still running after 50 years and more than 20,000 performances.

Sir Richard Attenborough, who was in the original production, participated in an anniversary performance: "It lasted so long because it is a bloody good play. Agatha Christie is very, very clever indeed."

Two of her novels were written at the height of her career, but held back until after her death: they were the last cases of Poirot and Miss Marple. As she did not want these characters to continue after her own death, both died in the course of these final books.